1. Field of the Invention
The present invention relates to a GPS navigation apparatus, and in particular relates to improvement in a function when a new route is created by use of point data, which has been specifically inputted by an operator to be stored as tracking data, together with movement locus data sequentially obtained in a tracking mode.
2. Description of the Related Art
A two-dimensional or three-dimensional positioning system using a radio wave from a GPS (global positioning system) satellite has been developed, and widely used as a navigation apparatus for automobiles, vessels, or the like. The GPS navigation apparatus is, together with an intrinsic navigation function, provided at least with a tracking function and a routing function.
Here, the tracking function is a function for displaying a movement state as locus information while positioning it at an interval of unit distance or unit time, and for preserving the locus data recorded from the start point to the destination (final arriving point), while the routing function is a function to have the destination and a special point previously inputted and stored by an operator based on a map, PIO (point of interest) information, or the like, such that a route from the start point to the destination is established to be displayed and preserved. The tracking function is often also provided with a function to preserve specific points, which are made to be inputted by the operator during a movement process, together with the locus data.
For example, when the tracking function is utilized in hiking, fishing, etc. by use of a vessel, or the like, the specific point is rarely known previously, and thus a WAY-POINT (specific point on a movement route) or MARK-POINT (specific point off the movement route) is sequentially inputted for storing by a user during actual movement.
In particular, a location of a forked route, well-water, or the like, in hiking, and a location of good fishing ground or the like in fishing, are stored as the WAY-POINT, and the location of a fine view or a position of an iron tower, lighthouse, headland, or the like, which was off the route but useful as a landmark, are stored as the MARK-POINT, together with ordinary movement locus data, respectively, for preserving as an original hiking or fishing route.
The route preserved by use of the tracking function as described above often contains useless routes between the start point and the destination. In other words, concerning the hiking course, there is a case where the destination is reached after repeatedly losing a way on the way, and a fishing vessel may largely meander to search for a good fishing ground, and thus an additional distance due to the lost way or meandered navigation is also included in the preserved route. Accordingly, when return-way navigation is executed by use of the route data preserved in an outward trip, or when the destination is visited later again using the preserved route, the route including the useless route is displayed, and the navigation can be made only along the displayed route.
Contrarily, when a route is created by linearly connecting the WAY-POINTs in the route, the navigation excluding the useless route becomes possible, and therefore there is a model with such a new route creating function. If a new route is created by linearly connecting only the MARK-POINTs, the navigation for visiting only impressive points is possible.
However, because the tracking function and the routing function in the GPS navigation apparatus are intrinsically independent, in order to create a route linearly connecting only the specific points as described above, required procedures are that a multiplicity of the start points, specific points and destinations, which are preserved and registered by the tracking function, are to be displayed as listed point information, only necessary points are selected and extracted therefrom, and data of the respective extracted points are transferred to the routing function to create the new route.
Specifically, although a procedure to execute is that the start points, specific points and destinations are selected one by one on a point listed picture screen of the tracking function, and the selected data is transferred to established information in the routing function in the conventional model, there is a recent model which can register as many as 600 points, and when a multiplicity of the specific points are registered with respect to a variety of routes, the point listed picture screen should be scrolled from one point to another, and the route creating operation becomes extremely complicated and troublesome in combination also with switching procedures of the function picture screen.
In particular, when the return route without useless route needs to be urgently created in case of worsening of weather, imminent sunset, or the like, it is extremely inconvenient, and may become a factor causing a disaster, or the like.